Having a tidy interface is certainly a primary goal but there are others. - Control over the size/shape of the sensor pad. - Control over communication (i2c/s

Having a tidy interface is certainly a primary goal but there are others. - Control over the size/shape of the sensor pad. - Control over communication (i2c/spi/usb) - Ability to explore gesture behaviors and expose simplified interfaces to the OS. - Control over click feel/behaviors by customizing snap switch style, mount, and locations. - Control over the touch surface finish. (Did you know you can laser cut glass screen protectors? Why are none of these touch pads glass outside of macbooks?) - Open documentation on all of the above. As for reading material I can't recommend anything as a summery (see my last bullet). Manufacture design guidelines are probably where you should start. Case in point: MTCH6301: https://www.microchip.com/wwwproducts/en/MTCH6301 https://www.microchip.com/wwwproducts/en/MTCH6301 Microchip Sensor design guide: http://ww1.microchip.com/downloads/en/DeviceDoc/FAQs%20-%20Sensor%20Design%20Guidelines.pdf http://ww1.microchip.com/downloads/en/DeviceDoc/FAQs%20-%20S...